Schedule of Amounts Reclassified Out of Other Comprehensive Earnings (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 27, 2013	Dec. 28, 2012
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Revenues	$ 711,502	$ 678,398
Earnings before taxes	142,366	138,163
Reclassification Out of Other Comprehensive Earnings
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Earnings before taxes	930	(23)
Reclassification Out of Other Comprehensive Earnings | Net Unrealized Gains (Losses) Defined benefit pension and post-retirement benefit plans
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Cost of Revenues & Operating Expenses	580	737
Reclassification Out of Other Comprehensive Earnings | Net Unrealized Gains (Losses) Cash Flow Hedging Instruments
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income On Derivatives [Line Items]
Revenues	$ 350	$ (760)